In many consumer products, it is desirable for perfume, especially perfume raw materials (“PRMs”) to be released slowly over time. Since the most volatile perfume raw materials, referred to as “top notes” are responsible for the “fresh smelling” consumers experience, it is desirable for the more volatile top notes to be released in a controlled and sustained manner. Moreover, top notes are often lost due to evaporation and/or dissolution in aqueous media.
One challenge for the formulators is to minimize the loss of top notes by exploring technologies that enhance the deposition of top notes on substrates, especially in the presence of water or when the substrate is subsequently exposed to water or moisture. Another challenge for the formulators is to control and extend the release of the deposited top notes so that the fresh smelling scent is not exhausted in a short burst.
Some recent developments to meet those challenges are directed to polymerizing the perfume, especially the perfume raw materials, into a polymeric particle; details of these developments are described in WO 01/79303 and EP 925,776. Other developments are directed to absorbing perfume into polymeric particles; details of these developments are described in U.S. Pat. No. 6,149,375; WO 00/68352; WO 98/28398 and WO 98/28339. These developments have failed to teach a polymeric particle that selectively absorbs/adsorbs top notes.
Accordingly, there is a need for perfume polymeric particles that selectively absorb/adsorb PRMs and efficiently deliver the PRMs to a substrate. Moreover, there is a need for perfume polymeric particles having a higher affinity for PRMs such that the amount of PRMs available for delivery to the substrate and for subsequent release is increased. There is a further need that such perfume polymeric particles, once deposited onto a substrate, provide a controlled, sustained release of the PRMs, especially the volatile top notes, over an extended period of time. There is also a need for compositions comprising such perfume polymeric particles such that the amount of PRMs remain with the perfume polymeric particles through the wash, rinse and drying is increased. Additionally, processes for making such perfume polymeric particles and compositions containing them are also needed.